Not applicable.
Not applicable.
The present invention relates to workpiece guides and, more particularly, to workpiece guides for cutting devices such as, for example, powered table saws. The present invention may be suitably adapted for use in connection with any device having a saw blade or other cutting member and wherein a workpiece is advanced into the cutting member in a controlled manner. Examples of possible applications of the workpiece guide of the present invention include use as a workpiece rip fence for a powered table saw.
Several known cutting devices include a cutting member such as, for example, a saw blade, that is at least partially surrounded by a workpiece support surface. In such devices, a workpiece is advanced along the workpiece support surface and into the driven cutting member to cut the workpiece. A familiar example of such a device is a powered table saw, which includes a rotating circular saw blade that is surrounded by a generally planar workpiece support surface or xe2x80x9csaw tablexe2x80x9d on which the operator slides the workpiece so as to contact the saw blade.
In order to accurately cut the workpiece to the desired dimensions, workpiece guides and other workpiece positioning devices are known. For example, miter gauges, rip fences, and workpiece jigs are available to accurately position a wooden workpiece relative to the saw blade of a table saw. Rip fence workpiece guides have long been used on table saws for providing a fixed guide surface against which the wooden workpiece can be positioned and advanced during ripping operations. Generally, known rip fences have included an elongated fence member having two opposed, parallel faces that extend across the saw table from the front of the saw (i.e., adjacent the typical position of the operator of the saw) to the rear of the saw and generally parallel to the plane of the circular saw blade. The rip fences have themselves been secured either solely to a guide bar attached and extending parallel to the front of the saw table or to a set of guide bars, one guide bar attached to each of the front and the back of the saw table. Commonly, the front guide bar includes a measuring scale so that the operator may ascertain the distance between the rip fence and the saw blade or other cutting member. Ripping of a workpiece may be conducted by advancing the workpiece into the cutting member along the saw table on either side of (i.e., to the left or right of) the cutting member therefore, and the guide bars typically extend along the saw table to either side of the cutting member so that the rip fence may be mounted at positions to the left and right of the cutting member.
An example of a rip fence that is secured solely to the front guide bar of a table saw is that described in U.S. Pat. No. 4,600,184, the entire disclosure of which is hereby incorporated herein by reference. The rip fence of the ""184 patent, which is partially shown in attached FIG. 9, includes a fence receiving member 10 and a workpiece fence 14 in the form of an elongated body having a number of workpiece guide surfaces on which a workpiece may by advanced during ripping operations. To accommodate placement of the ""184 patent""s rip fence to either side of the cutting member, the workpiece fence 14 may be releasably secured to either side of the fence receiving member 10 by a workpiece fence attachment system including knobs 16, fasteners 20, and plate 26. By threadedly advancing knobs 16 onto threaded fasteners 20 disposed through fence receiving member 10, wall 24 of the fence 14 may be securely clamped between the fence receiving member 10 and plate 26. The knobs 16, fasteners 20, and plate 26 are shown in FIG. 9 in positions appropriate for placement of the rip fence of the ""184 patent to the right side of the cutting member, as that position is viewed from the typical position of an operator standing in front of the table saw. When ripping stock on the opposite side of the cutting member, the knobs 16 are unthreaded from the fasteners 20, the fasteners 20 are removed from the fence receiving member 10, and the orientation of the fasteners 20 and plate 26 is reversed so that the plate 26 is positioned on the opposite side of the fence receiving member 10. The workpiece fence 14 is then repositioned so that wall 24 is disposed between the plate 26 and the fence receiving member 10, but on the opposite side of the fence receiving member 10. The knobs 16 are then re-threaded securely onto the fasteners 20 so that the wall 24 is secured between the plate 26 and the fence receiving member 10.
Although the rip fence of the ""184 patent allows the fence and its workpiece guide surface to be positioned on either side of the cutting member, repositioning the fence from one to another side of the fence receiving member requires unthreading the knobs 16 and reversing the arrangement of the knobs 16, fasteners 20, and plate 26. When a series of workpieces are being ripped on alternate sides of the cutting member, the unthreading and repositioning procedure may need to be repeated a number of times. Therefore, it may be desirable to reduce the time and number of steps that is required to reposition the workpiece fence of the rip fence.
Accordingly, it would be advantageous to provide a table saw rip fence having a positionable workpiece guide surface that may be quickly and easily repositioned to allow ripping on opposite sides of the table saw""s cutting member. More generally, and because a rip fence only represents one possible adaptation of a workpiece guide, it would in a broader sense be advantageous to provide a workpiece guide having a positionable workpiece guide surface that may be quickly and easily repositioned. Thus, a need exists for an improved workpiece guide providing such advantages.
The present invention addresses the forgoing needs, among others, by providing an improved workpiece guide including a fence receiving member having first and second sides. A first mounting member is disposed adjacent the first side, and a second mounting member is disposed adjacent the second side. An attachment system is mounted on the fence receiving member and is connected to both the first and second mounting members, and the attachment system may selectively simultaneously bias the first mounting member toward the fence receiving member""s first side and the second mounting member toward the fence receiving member""s second side.
In one embodiment, the attachment system includes a plurality of linking members and at least one link receiving member. A first linking member is connected to the first mounting member, a second linking member is connected to the second mounting member, and both the first and the second linking members are connected to the link receiving member. The link receiving member may be manipulated to selectively simultaneously bias the first and second mounting members toward the link receiving member. Preferably, rotation of the link receiving member selectively simultaneously biases the first and second mounting members toward the link receiving member.
The workpiece guide of the present invention also may include a fence having a workpiece guide surface and an attachment portion. The attachment portion may be positioned intermediate the first mounting member and the first side of the fence receiving member or, in the alternative, intermediate the second mounting member and the second side. The link receiving member is manipulated, and preferably is rotated, to selectively secure the attachment portion of the fence in the selected intermediate position. In that way, the fence may be secured against one of the first side and the second side of the fence receiving member.
The present invention also is directed to a workpiece guide including a fence receiving member having first and second sides, a first mounting member disposed adjacent the first side, and a second mounting member disposed adjacent the second side. First and second linking members are connected to the first and second mounting members, respectively, and a first link receiving member is connected to both the first and second linking members and may selectively simultaneously bias the first and second mounting members toward or away from the first link receiving member. In one form, the first and second linking members each include a threaded region and the first link receiving member threadedly receives at least a portion of the threaded region of each of the first and second linking members. By that arrangement, rotation of the link receiving member in a particular direction may cause the first and second linking members to either simultaneously threadedly advance into or simultaneously threadedly withdraw at least some extent from the first link receiving member, thereby varying a distance between the first and second mounting members. Preferably, the threaded region of one of the first and second linking members includes right hand threads and the threaded region of the other of the first and second linking members includes left hand threads to thereby provide for the simultaneous advancement or withdrawal.
The workpiece guide of the invention may further include at least third and fourth linking members, each including a threaded region. The third and fourth linking members are connected to the first and second mounting members, respectively, and also are threadedly connected to a second link receiving member. Movement, and preferably rotation, of the second link receiving member in a particular direction causes the third and fourth linking members to either simultaneously threadedly advance into or simultaneously threadedly withdraw at least some extent from the second link receiving member, to thereby vary a distance between the first and second mounting members. Any number of additional linking members and link receiving members also may be provided. For example, the workpiece guide may include a total of eight linking members, four connected to each mounting member, and with four link receiving members, each attached to two link members.
The first and second mounting members may be, for example, bars or plates, and each linking member may be, for example, a bolt or stud having a first end (which may include the threaded region) and a second end connected to one of the mounting members. In such form, it is preferred that each stud is disposed through the side of the fence receiving member adjacent the plate to which the particular stud or bolt is attached.
The first link receiving member and the second link receiving member may be connected by a transmission or a linkage, and rotation of the first link receiving member is transmitted through the transmission or linkage to cause rotation of the second link receiving member in the same direction of rotation. A lever may be attached to one of the link receiving members to facilitate rotation of the link receiving member by an operator. The fence receiving member preferably defines a cavity in which the first and second link receiving members are disposed. Any additional link receiving members may be similarly connected by a transmission or linkage and/or disposed in the cavity.
In one form, the workpiece guide of the present invention is adapted for use as a rip fence that may be selectively attached to a guide bar of a table saw. As further described in the following detailed description of embodiments of the invention, the construction of the present workpiece guide allows the fence to be repositioned on the fence receiving member without the removal of knobs or fasteners as in the prior art ""184 patent. It therefore may provide the advantage of reducing the number of steps involved in detaching and reattaching the fence, thereby quickening the fence repositioning process. Thus, when the present invention is adapted for use as a table saw rip fence, the workpiece fence, which includes a workpiece guide surface, may be easily and conveniently repositioned to allow for ripping operations on either side of the saw blade.
The reader will appreciate the foregoing details and advantages of the present invention, as well as others, upon consideration of the following detailed description of embodiments of the invention. The reader also may comprehend such additional details and advantages of the present invention upon using the invention.